In the US, service charges are usually not included in the bill.  Waitresses and taxi cab drivers are usually tipped 15-20% of the bill.  Some people also tip barbers and hair stylists a dollar or two.  If you do not carry your own luggage, bellboys and porters receive $1.00 for each piece of luggage.  No tips are given to theater ushers, airline personnel, gas station attendants, or "baggers" in grocery stores.

University News
March 19, 2018
A new exhibition in Cowles Library examines the life and work of Jay N. “Ding” Darling, two-time Pulitzer-prize winning political cartoonist and environmental conservationist.